Microsoft has fixed performance issues impacting gamers running Windows 10 21H1 and 20H2 with the latest Windows 10 build released for Insiders in the Beta and Release Preview Channel. Issues primarily impacted systems running games in full screen or borderless windowed modes on two or more displays. Problems experienced while playing games on affected systems include video stuttering, decreased frame rate, flickering textures, and flickering textures. Microsoft has also fixed an issue that prevents sorting from working properly when using multiple versions of National Language Support (NLS) sorting.
Source: https://www.bleepingcomputer.com/news/microsoft/windows-10-kb5003690-fixes-issues-affecting-gamers-since-march/